Masking strip



Oct. 28, 1930. O DOTY ET AL 1,779,588

MASKING STRIP Filed June 22, 1927 ll l INVENTORS ,f hn QDaty and.

BY Paul C. Orauib f ATTORNEYS Patented Oct. 28, 1930 UNITED STATES PATENT orrlce JOHN CHER DOTY AN D PAUL (J. OBCU TT, OI INDIANAPOLIS, INDIANA.

nasxmo s'rnn' Application filed lane 22,

The objects of our invention is to produce a new article of manufacture, which may be conveniently referred to as a masking strip for facilitating the accurateapplication, by spray devices, or otherwise, of paints, varnishes, lacquers, etc., to articles such, for mby means of a spray gun, requires the proteccompleted the tape is stripped from the surtion of various portions of the body, at different times, from the spray, the application of which cannot be accurately controlled by the spray gun itself. For this purpose it has been customary, recently, to use an adhesive tape, quite like the well known surgical adhesive tape. The common practice, especially where the work is being performed by a single workman, is to cause the tape to adhere, by light pressure along a line immediatel ad'acent the surface which is to be coate he ve edge of this tape is then lifted slightly an a sheet of paper of desired extent inserted beneath it and the tape then pressed to place. The sheet of paper will have suflicient width and extent to thoroughly protect the surface which is to be protected and when the application of color has been face and thrown away because the adhesive material carried by the tape is of such character that having been once applied to any surface, it does not again firmly adhere to another surface. Occasionally a second use of the tape may be had, but not often. The application of proper masks to a job, such as an automobile body, by the above described "means and method is a tedious and time consuming operationand is also fairly expensive because of the limited usability of the adhesive tape.

The object of our present invention is .to provide a masking strip of such character that it may be readily and quickly applied to surfaces to be masked and such that 1t may be repeatedly used upon successive jobs.

The accompan 'ng drawing illustrates our invention, 10 indicating a sheet or strip of paper or other suitable flexible and protec tive material, of convenient width, say about 1927. sci-m1 No. 200,550.

9" more or less, and car a comparatively narrow str1 11 of an adhesive material preferably 0 such character that it may be firmly associated with the paper strip and, when applied. with light pressure and atnormal temperatures, will adere firmly against a lateral displacement in the plane of the sheet, 'to man successive surfaces to which it-may be apphed, yet may be readily stripped from such surfaces.

While there may be many compositions of matter which will possess the desired ad-' hesive qualities and which will retain, such qualities for extended periods of time and through many successive applications to surfaces vto be protected, our present knowledge has lead us to the belief that the most satislowing manner:

Assuming that approximately 100 lbs. of adhesive material is desired we take-60.25 lbs. of commercial, rubber hydrocarbon to which we add suflicient benzole, say about 5 lbs., to produce a liquid of about the consistency of whipping cream. To this we add 15.46 1 s. of zinc oxide stirring thoroughly until a doughy mass hasbeen produced. We then add, without regard to order of addition, 8.95 lbs. of organic acetone, 1.11 lbs. chloroform, 8.20 lbs. sulphur-and 1.03 lbs. parafline oil, stirring the mass until it is thoroughly mixed and forms a dough-like mass which is then rolled between polished rollers to a desired width and thickness, say from to 1" wide and about 0.003 in thickness and applied to a strip of Holland or other protective material which will strip readily therefrom. The exposed surface of the adhesive is then slightly moistened with benzole and then exposed surface is then applied,- with considerable pressure to the desired portion of the paper strapl 10.

The application of the a esive to the paper in the above described manner causes such an intimate contact between the paper and the adhesive that the adhesive cannot be readily separated from the paper. If desired the Holland may then be stripped from the adhesive and the sheet rolled into convenient form for shipping and handling. Care must factory results may be obtained in thefolupon one edge be exercised not to bring two portions of the exposed face of the adhesivetogether because ever, the ex osed surface of the adhesivewill adhere slig tly to the paper as it is-rolled but will readily strip therefrom upon unrolling.

In use our prepared mask strip may be very readily and quic 1y applied by a single workman and will be firmly held in place against all movement or removal by a stri ping force at right angles to the surface. T e paper is wide enough to afford ample protection of the surface adjacent that to which the color is to be applied. As soon as the need for the mask is passed the mask may be readily stripped from place andre-rolled for use in a subsequent operation. We have found that when the adhesive is made in the manner hereinbefore set forth itwill still be serviceable after may operations even though the strip has not been rolled and the adhesive has theretofore been left open to the atmosphere.

In course of time the edge of the strip along the outer edge of the adhesive is apt to become somewhat uneven because of unour hands at Indianapolis, Indiana, this 20th day of June, A. D. one thousand nine hundred and twenty-seven.

' JOHN OMER DOTY.

PAUL C. ORCUTT.

even accumulation of the paint, varnish or lacquer and then unevenness is apt to occur long before the adhesive has reached a condition where it is no longer readily adhesable to surfaces to be protected. Consequently, while a comparatively narrow strip of adhesive is suflicient to successfully hold the paper against displacement, it is quite desirable that it be originally of sufficient width to permit occasional trimming so that a fresh sharp edge may be presented along the line up to which the desired color is to be applied.

We claim as our invention:

1. As an article of manufacture a masking strip comprising a sheet of paper of substantial width and of a length substantially greater than the width provided-along one lengthwise edge with a narrow strip of adhesive, said adhesive strip being of such character and width as to firmly adhere to the sheet, and to be successively adhesable to a substantial number of surfaces to be protected in such manner as to firmly retain the sheet against displacement in its own plane but to be readily Withdrawn from such surface by a stripping force applied at an angle to said surface.

2. As an article of manufacture a masking strip consisting of a strip of flexible protective material of substantial width provided along one edge with a narrow strip of adhesive firmly secured thereto, said adhesive being composed of rubber hydrocarbon, organic acetone, chloroform, zinc oxide, sulphur, parafline oil and benzole.

In witness whereof, we have hereunto set DISCLAIMER 1,77 9,588.-John Omer Doty and Paul 0'. Orcutt, Indianapolis, Ind. MASKING STRIP. Patent dated October 28, 1930. Disclaimer filed January 17, 1942, by the assignee,"Minnesota Mining (2: Manufacturing 00.

Hereby enters this disclaimer to claim 1 of said patent.

[Ofiicial Gazette August 4, 1942.] 

